The present invention relates to a catheter used for angiocardiography and curing the heart or its peripheral tissues, particularly, to a catheter for coronary arteries.
Known catheters for coronary arteriography include Judkins type, Anplatzs type, etc. In general, these catheters are pierced from a femoral artery by Seldinger technique or sheath technique for selective coronary arteriography.
Treatment using a catheter is also widely employed nowadays including, for example, percutaneous transluminal coronary angioplasty (PTCA) using a balloon-tip catheter for the treatment of ischemic heart diseases. For inserting a treating catheter efficiently and with safety into a desired blood vessel, the performance of the treating catheter is very important. For example, it is necessary to use together a guiding catheter which permits alleviating the reaction brought about by the insertion of the treating catheter and also permits imparting a sufficient back-up force to the treating catheter so as to provide an effective assistance for smooth insertion of the treating catheter. Like the catheter for coronary arteriography, the known guiding catheters also include Judkins type, Anplatzs type, etc. In general, the guiding catheter is inserted from the femoral artery by Seldinger technique or sheath technique to selectively secure the coronary arteries, followed by inserting a treating catheter such as a balloon-catheter for PTCA within the guiding catheter.
In the conventional angiography or treatment using a catheter, a femoral region is pierced by the catheter and hemostasis is applied to the piercing portion after the operation. Therefore, the patient is required to lie absolutely quiet, leading to a serious problem. For example, it is necessary for the patient to urinate, evacuate, and take food and drink while lying on his back so as to give considerable pains such as pains in the waist portion to the patient. Further, where the catheter is pierced from the femoral region, bleeding is likely to take place even if the patient keeps quiet. If the bleeding reaches the cavitas peritonealis, the patient's life is endangered. Still further, urination while lying on the back is made difficult in some cases. A urinary tract catheter is used in this case. However, use of the particular catheter tends to bring about a urinary tract infectious disease.
For eliminating or suppressing these problems, it is considered effective to pierce a catheter from an artery in the arm, particularly, a brachial artery, or a radial artery. If the catheter is pierced from an artery in the arm, the patient is able to walk immediately after the operation by simply keeping the piercing portion in the upper arm portion stretched. Also, the patient is free from pains in the waist portion and able to urinate, evacuate and take food and drink as usual. Further, the urinary tract infectious disease in the cavitas peritonealis need not be worried about.
However, the catheter should originally be designed to have a shape adapted for the piercing portion. Since the catheter generally used nowadays is designed to be introduced from the femoral artery, a catheter adapted for introduction from an artery in the arm promptly and with safety is unknown to the art. Suppose the catheter for introduction from the femoral artery is used as it is for introduction from the brachial artery. In this case, the catheter introduction is made difficult and troublesome, making it necessary to perform the introducing operation repeatedly. Naturally, the operating time is increased so as to increase the burden given to the patient. Further, since the back-up force is insufficient, the distal end of the catheter fails to be introduced into the entrance of the coronary artery during the imaging operation or when the treating catheter is moved toward the peripheral sites. It follows that a sufficient angiography cannot be performed, or operation of the treating catheter is made difficult.
Under the circumstances, it is strongly required to develop a catheter of a shape adapted for introduction from the arm of the patient.